The signaling mechanisms that regulate cell migration are not well understood despite its importance in numerous biological and pathological processes, including embryogenesis, the inflammatory response, tissue repair and regeneration, cancer, arthritis, atherosclerosis, osteoporosis, and congenital developmental brain defects. An emerging concept is that molecules, which integrate signaling components to coordinately regulate processes underlying migration, such as actin reorganization, adhesion assembly and disassembly (turnover), and the establishment of polarity, are critical for this process. We hypothesize that the multi-domain containing protein, Asef2, functions in this capacity by integrating critical signaling components of these processes to regulate cell migration. Our preliminary work has lead to working hypotheses and the objective of this proposal is to rigorously test these hypotheses as outlined in the specific aims. Specific Aim I will test the hypothesis that Asef2 is a critical regulator of migration through its ability to integrate molecular signals, which are important to this process. We will determine the domains that mediate this function of Asef2 to gain insight into the molecular mechanisms by which it regulates cell migration. In Specific Aim II, we will test the hypothesis that Asef2 brings together kinases, such as Akt, and Rho family GTPase signaling to modulate cell migration. In this aim, we will use expression constructs, mutant based strategies, pharmacological inhibitors, and siRNA studies to test this hypothesis. Our working model is that Asef2 signaling coordinately regulates the activities of kinases and Rho GTPases to stimulate the rapid turnover of leading edge adhesions, which leads to enhanced cell migration. Specific Aim III will determine if Asef2 signaling components, such as Akt and other kinase effectors, regulate the turnover of leading edge adhesions. In this aim, we will test our hypothesis by using new quantitative assays that we developed to study adhesion turnover. The studies outlined in this proposal will lead to a greater understanding of the signaling mechanisms by which Asef2 regulates cell migration. PUBLIC HEALTH RELEVANCE: Cell migration is central to many biological and pathological processes, such as cancer, arthritis, atherosclerosis, and congenital brain defects. Understanding the molecules that regulate migration will lead to new therapeutic approaches to treating these disorders. The goal of this proposal is to identify molecules that are critical regulators of cell migration.